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Quantifying spatiotemporal variability in occupant exposure to an indoor airborne contaminant with an uncertain source location

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Building Simulation 2023年第6期16卷 889-913页

作者： john e.Castellini Jr Cary A.Faulkner Wangda Zuo Michael D.Sohn Department of Mechanical engineering University of Colorado BoulderUCB 427BoulderCO80309USA Department Architectural engineering The Pennsylvania State UniversityUniversity ParkPA16802USA National Renewable energy National Laboratory GoldenCO80401USA energy Analysis and environmental Impacts Division Lawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA94720USA

Well-mixed zone models are often employed to compute indoor air quality and occupant *** effective,a potential downside to assuming instantaneous,perfect mixing is underpredicting exposures to high intermittent concentrations within a *** such cases are of concern,more spatially resolved models,like computational-fluid dynamics methods,are used for some or all of the ***,these models have higher computational costs and require more input information.A preferred compromise would be to continue with a multi-zone modeling approach for all rooms,but with a better assessment of the spatial variability within a *** do so,we present a quantitative method for estimating a room’s spatiotemporal variability,based on influential room *** proposed method disaggregates variability into the variability in a room’s average concentration,and the spatial variability within the room relative to that *** enables a detailed assessment of how variability in particular room parameters impacts the uncertain occupant *** demonstrate the utility of this method,we simulate contaminant dispersion for a variety of possible source *** compute breathing-zone exposure during the releasing(source is active)and decaying(source is removed)*** CFD methods,we found after a 30 minutes release the average standard deviation in the spatial distribution of exposure was approximately 28%of the source average exposure,whereas variability in the different average exposures was lower,only 10%of the total *** also find that although uncertainty in the source location leads to variability in the average magnitude of transient exposure,it does not have a particularly large influence on the spatial distribution during the decaying period,or on the average contaminant removal *** systematically characterizing a room’s average concentration,its variability,and the spatial variability within the room important insights can be gain

关键词： uncertainty variability airborne contaminant spatiotemporal variability well-mixed heterogeneity

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Hospitalized prevalence and 5-year mortality for IBD:Record linkage study

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World Journal of Gastroenterology 2010年第4期16卷 431-438页

作者： Lori A Button Stephen e Roberts Michael J Goldacre Ashley Akbari Sarah e Rodgers john G Williams School of Medicine Swansea UniversitySwansea SA2 8PPUnited Kingdom Unit of Health-Care epidemiology University of OxfordOxford OX2 7LFUnited Kingdom

AIM:To establish the hospitalized prevalence of severe Crohn's disease(CD) and ulcerative colitis(UC) in Wales from 1999 to 2007;and to investigate long-term mortality after hospitalization and associations with social deprivation and other socio-demographic ***:Record linkage of administrative inpatient and mortality data for 1467 and 1482 people hospitalised as emergencies for ≥ 3d for CD and UC,*** main outcome measures were hospitalized prevalence,mortality rates and standardized mortality ratios for up to 5 years follow-up after ***:Hospitalized prevalence was 50.1 per 100 000 population for CD and 50.6 for *** hospitalized prevalence of CD was significantly higher(P emales(57.4) than in males(42.2),and was highest in people aged 16-29 years,but the prevalence of UC was similar in males(51.0) and females(50.1),and increased continuously with *** hospital-ized prevalence of CD was slightly higher in the most deprived areas,but there was no association between social deprivation and hospitalized prevalence of *** was 6.8% and 14.6% after 1 and 5 years follow-up for CD,and 9.2% and 20.8% after 1 and 5 years for *** both CD and UC,there was little discernible association between mortality and social deprivation,distance from hospital,urban/rural residence and ***:CD and UC have distinct demographic *** higher prevalence of hospitalized CD in more deprived areas may reflect higher prevalence and higher hospital dependency.

关键词： Crohn’s disease Ulcerative colitis Prevalence Mortality Record linkage

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Natural regeneration responses to thinning and burning treatments in ponderosa pine forests and implications for restoration

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Journal of Forestry Research 2022年第3期33卷 741-753页

作者： Tzeidle N.Wasserman Amy e.M.Waltz john Paul Roccaforte Judith D.Springer Joseph e.Crouse ecological Restoration Institute Northern Arizona UniversityP.O.Box 15017FlagstaffAZ86011-5017USA

Understanding naturally occurring pine regeneration dynamics in response to thinning and burning treatments is necessary not only to measure the longevity of the restoration or fuels treatment,but also to assess how well regeneration meets forest sustainability guidelines and whether natural regeneration is sufficient for maintaining a sustainable forest structure and composition.A synthesis review was carried out on the effects of mechanical thinning and prescribed burn treatments on natural pine regeneration response in frequent-fire ponderosa pine forests across the western United *** focus was on site-specific variability in pine regeneration dynamics,temporal trends in regeneration presence and abundance,and response to treatment as described in the current literature using 29 studies that met our evidence-based review *** showed that the effects of thinning and burning treatments on regeneration depended on time since *** thinning,prescribed burning,and thinning plus burn treatments all increased seedling density,but there was high variability among sites and *** were mixed results in the short-term(ears)with both increasing and decreasing regeneration,and a general increase in regeneration 11−20 years *** long-term studies(>20 years)concluded that stands can return to pre-treatment densities in terms of total trees per hectare and forest floor duff levels when there are no maintenance treatments *** studies showed the average ponderosa pine seedling presence,survival and growth found in today’s forests to be at a high density;this combined with missed fire cycles could contribute to future fire risk and reduce the efficacy of maintaining fuel reduction goals.

关键词： Regeneration Ponderosa pine Frequent-fire Treatments Thinning Burning

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Longwave infrared multispectral image sensor system using aluminum-germanium plasmonic filter arrays Noor e

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Nano Research 2023年第7期16卷 10018-10025页

作者： Karishma Shaik Bryce Widdicombe Dechuan Sun Sam e john Dongryeol Ryu Ampalavanapillai Nirmalathas Ranjith R Unnithan Department of electrical and electronic engineering University of MelbourneParkvilleVIC 3010Australia Department of Biomedical engineering University of MelbourneParkvilleVIC 3010Australia Department of Infrastructure engineering University of MelbourneParkvilleVIC 3010Australia

A multispectral camera records image data in various wavelengths across the electromagnetic spectrum to acquire additional information that a conventional camera fails to *** the advent of high-resolution image sensors and color filter technologies,multispectral imagers in the visible wavelengths have become popular with increasing commercial viability in the last ***,multispectral imaging in longwave infrared(LWIR,8-14μm)is still an emerging area due to the limited availability of optical materials,filter technologies,and high-resolution *** from LWIR multispectral cameras can capture emission spectra of objects to extract additional information that a human eye fails to capture and thus have important applications in precision agriculture,forestry,medicine,and object *** this work,we experimentally demonstrate an LWIR multispectral image sensor with three wavelength bands using optical elements made of an aluminum(Al)-based plasmonic filter array sandwiched in germanium(Ge).To realize the multispectral sensor,the filter arrays are then integrated into a three-dimensional(3D)printed wheel stacked on a low-resolution monochrome thermal *** prototype device is calibrated using a blackbody and its thermal output has been enhanced with computer vision *** applying a state-of-theart deep learning method,we have also reconstructed multispectral images to a better spatial ***,our work demonstrates a versatile spectral thermography technique for detecting target signatures in the LWIR range and other advanced spectral analyses.

关键词： infrared plasmonics germanium(Ge) aluminum(Al) thermal optics longwave infrared(LWIR)multispectral system

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Femoral impaction grafting

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World Journal of Orthopedics 2013年第1期4卷 7-11页

作者： john A Scanelli Thomas e Brown Department of Orthopedic Surgery University of Virginia School of Medicine Charlottesville VA 22908 United States

Femoral impaction grafting is a reconstruction option applicable to both simple and complex femoral component revisions. It is one of the preferred techniques for reconstructing large femoral defects when the isthmus is non-supportive. The available level of evidence is primarily derived from case series, which shows a mean survivorship of 90.5%, with revision or re-operation as the end-point, with an average follow-up of 11 years. The rate of femoral fracture requiring re-operation or revision of the component varies between several large case series, ranging from 2.5% to 9%, with an average of 5.4%.

关键词： Femoral impaction grafting Femoral revision Bone grafting Revision total hip arthroplasty Bone loss

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Tolerance to individual and joint effects of arsenic and Bacillus thuringiensis subsp, israelensis or Lysinibacillus sphaericus in Culex mosquitoes

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Insect Science 2014年第4期21卷 477-485页

作者： Christina L. Mogren William e. Walton john T. Trumble Department of entomology University of California Riverside CA 92521 USA

Arsenic contamination of global water supplies has come to the forefront in policy decisions in recent decades. However, the effects of arsenic on lower trophic levels of insects inhabiting contaminated ecosystems are not well understood. One approach to document both acute and sublethal effects of toxicants like arsenic is to assay them in combination with microbial pathogens to evaluate shifts in survival curves of the test organisms. Larvae of Culex quinquefasciatus and Culex tarsalis were reared in water containing 0 or 1 000μg/L of arsenate or arsenite. Fourth instars were then exposed to a range of doses of Bacillus thuringiensis subsp, israelensis （Bti） or Lysinibacillus sphaericus （Ls）, with shifts in lethal concentrations determined. Arsenic accumulation in 4th instars was also quantified, and a relative growth index （RGI） calculated for the treatments and compared to controls. Larvae of both species accumulated between 4 447 ± 169 ng As/g and 6 983 4- 367 ng As/g, though RGI values indicated accumulation did not affect growth and development. In all cases, the LC50＇s and LC90＇s of Cx. quinquefasciatus exposed jointly with arsenic and Bti/Ls were higher than Cx. tarsafis. Cx. tarsafis reared in arsenite showed a significant reduction in their Bti LC90 values compared to the control, indicating a sublethal effect of Bti. When exposed jointly with Ls, arsenite was more toxic than arsenate in Cx. tarsalis. Overall, these results indicate tolerance of these Culex species to arsenic exposures, and why this may occur is discussed.

关键词： arsenate arsenite Bsph Bti Culex tarsalis Culex quinquefasciatus

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Polarization variability arising from clumps in the winds of Wolf-Rayet stars

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Chinese Journal of Astronomy and Astrophysics 2009年第5期9卷 558-576页

作者： Qing-Kang Li Joseph e Cassinelli john C. Brown Richard Ignace Department of Astronomy Beijing Normal University Beijing 100875 China Department of Astronomy University of Wisconsin-Madison 53711 USA Department of Physics and Astronomy University of Glasgow Glasgow G12 8QQ Scotland UK Department of Physics and Astronomy Eastern Tennessee State University USA

Polarimetric and photometric variability of Wolf-Rayet （WR） stars as caused by clumps in the winds is revisited. In our model, which is improved from Li et al., radial expansion of the thickness is accounted for, but we retain dependence on the β velocity law and stellar occultation effects. We again search for parameters that can yield results consistent with observations in regards to the mean polarization p, the ratio R = σp/σphot of polarimetric to photometric variability and the volume filling factor fV. Clump generation and spatial distribution are randomized by the Monte Carlo method so as to produce clumps which are, in the mean, distributed uniformly in space and have time intervals that obey a Gaussian distribution. The generated clumps move radially outward with a velocity law determined by a β index, and the angular size of clumps is assumed to be fixed. By fitting the observed σp/σphot and the volume filling factor fv, clump velocity taw index β （- 2） and clump ejection rate .N （- 1） are inferred, and are found to be well constrained. In addition, the subpeak features of broad emission lines seem to support the clump ejection rate. Meanwhile, the fraction of total mass loss rate that is contained in clumps is obtained by fitting observed polarization. We conclude that this picture of the clumps＇ properties produces a valuable diagnostic of WR wind structure.

关键词： stars mass loss -- stars Wolf-Rayet -- stars winds, outflows

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Modelling of phosphorus accumulation in an aeroponic coriander crop

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International Journal of Agricultural and Biological engineering 2022年第6期15卷 73-79页

作者： Alejandro Rincón Santamaría john e.Candelo-Becerra Fredy e.Hoyos Velasco Grupo de Investigación en Desarrollos Tecnológicos y Ambientales-GIDTA Facultad de Ingeniería y ArquitecturaUniversidad Católica de Manizales170002 ManizalesColombia Grupo de Investigación en Microbiología y Biotecnología Agroindustrial-GIMIBAG Instituto de Investigación en Microbiología y Biotecnología AgroindustrialFacultad de Ciencias de la SaludUniversidad Católica de Manizales170002 ManizalesColombia Department of electrical energy and Automation Faculty of MinesUniversidad Nacional de ColombiaSede MedellínMedellín 050041AntioquiaColombia

A model was developed for phosphorus(P)concentration over time in a closed aeroponic coriander *** addition,the setting and starting up of the soilless culture is described,and the measurements of electrical conductivity(eC),pH and concentration of major ions in the mixing tank are *** using mass balance principles,the dynamics of the nutrient concentration in the mixing tank and in the drainage solution are *** series of continuous stirred tank reactors are considered for the flow structure,using a power law relationship to represent the rate of nutrient removal,considering water volume *** concentration measurements were used for model fitting,and the resulting simulation is in good agreement with data.

关键词： aeroponic culture hydroponics soilless culture nutrient modelling Coriander sativum

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Simulating hydraulic fracturing processes in laboratory-scale geological media using three-dimensional TOUGH-RBSN

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Journal of Rock Mechanics and Geotechnical engineering 2018年第6期10卷 1102-1111页

作者： Daisuke Asahina Pengzhi Pan Kimikazu Tsusaka Mikio Takeda john e.Bolander Geological Survey of Japan IbarakiJapan State Key Laboratory of Geomechanics and Geotechnical engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China INPeX Corporation TokyoJapan University of California DavisUSA

In this context, recent developments in the coupled three-dimensional(3 D) hydro-mechanical(HM)simulation tool TOUGH-RBSN are presented. This tool is used to model hydraulic fracture in geological media, as observed in laboratory-scale tests. The TOUGH-RBSN simulator is based on the effective linking of two numerical methods: TOUGH2, a finite volume method for simulating mass transport within a permeable medium; and a lattice model based on the rigid-body-spring network(RBSN) concept. The method relies on a Voronoi-based discretization technique that can represent fracture development within a permeable rock matrix. The simulator provides two-way coupling of HM processes, including fluid pressure-induced fracture and fracture-assisted flow. We first present the basic capabilities of the modeling approach using two example applications, i.e. permeability evolution under compression deformation, and analyses of a static fracturing simulation. Thereafter, the model is used to simulate laboratory tests of hydraulic fracturing in granite. In most respects, the simulation results meet expectations with respect to permeability evolution and fracturing patterns. It can be seen that the evolution of injection pressure associated with the simulated fracture developments is strongly affected by fluid viscosity.

关键词： Hydraulic fracture Crack opening TOUGH Rigid-body-spring network(RBSN) Permeability Injection pressure Fluid viscosity Hydro-mechanical(HM) processes

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explicit and Parameterized episodes of Warm-Season Precipitation over the Continental United States

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Advances in Atmospheric Sciences 2006年第1期23卷 91-105页

作者： Mitchell W. MONCRIeFF john D. TUTTLe Richard e. CARBONe National Center for Atmospheric Research BoulderColorado 80307-3000U. S. A.

This paper describes explicit and parameterized simulations of midsummer precipitation over the continental United States for two distinct episodes： moderate large-scale forcing and weak forcing. The objective is to demonstrate the capability of explicit convection at currently affordable grid-resolution and compare it with parameterized realizations. Under moderate forcing, 3-kin grid-resolution explicit simulations represent rainfall coherence remarkably well. The observed daily convective generation near the Continental Divide and the subsequent organization and propagation are reproduced qualitatively. The propagation speed, zonal extent and duration of the rainfall streaks compare favorably with their observed counterparts, although the streak frequency is underestimated. The simulations at -10-km grid-resolution applying conventional convective parameterization schemes also replicate reasonably well the diurnal convective regeneration in moderate forcing. The performance of the 3-km grid-resolution model demonstrates the potential of -1-km-resolution explicit cloud-resolving models for the prediction of warm season precipitation for moderately forced environments. In weak forcing conditions, however, predictions of precipitation coherence and diurnal variability are much poorer. This suggests that an even finer resolution explicit model is required to adequately treat convective initiation and upscale organization typical of the warm season over the continental U.S.

关键词： warm-season precipitation explicit simulation convective parameterization

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